The Muscular and Skeletal SystemsWarm-up:

•Have you ever have had an injury to a muscle? Or broken a bone? What happened? How long did it take to heal? What type of treatment did you have to do?

The Human Body Book—Muscular System

• “The muscular system produces an endless variety of actions by using muscles as coordinated teams. Muscle tissue creates bodily movements and it also powers internal processes, from the heartbeat to the movement of food through the intestines, the adjustment of artery diameter to the focusing of the eye. The muscular system leads a very physical existence, in which regular use prevents wasting, and injury is more common than disease. However, muscles are helpless without the nervous system to stimulate and integrate their activity.”

Muscular System

• The function of the muscular system is to contract and relax your muscles. • It allows your body to move.

• There are approximately 640 muscles in the body. About 42% muscle mass in males. About 36% muscle mass in females.

• All muscles bear Latin names that describe one or more aspects of their shape, structure, or origin. • Flexor/Extensor; longus/maximus/minimus

What Muscles Do!• The muscular system allows you to move voluntarily

or involuntarily.• Voluntary MusclesVoluntary Muscles

• Muscles that you are in control of and allow your body to move, such as pick up a ball, or walk across a room.

• What are some voluntary muscles you know?

• Involuntary MusclesInvoluntary Muscles

• Muscles that work automatically rather than under conscious control.

• They control such actions as breathing, digestion, and most importantly your heart beat.

How Muscles Work

• A muscle is made up of hundreds of long cells called muscle fibers.

• Major muscles in the body are made up of hundreds of bundles of these fibers.

• When these bundles are stimulated by nerve impulses, or signals, they contract, or shorten.

• When they relax, the bundles extend, or stretch.

Types of Muscles• There are three types of muscles:• Smooth musclesSmooth muscles• Muscles that act on the lining of the body’s passageways

and hollow internal organs.• Can be found in the digestive tract, the urinary bladder, the

lining of the blood vessels, etc. • They are involuntary muscles.

• Cardiac muscleCardiac muscle• A type of striated muscle that forms the wall of the heart.• Involuntary muscle.• Responsible for contraction of the heart.

Types of Muscles

• Skeletal MusclesSkeletal Muscles• Muscles that are attached to bone.• Voluntary muscles• Skeletal muscles often work together in pairs to

produce movement. One muscle contracts while the other relaxes.

• What skeletal muscles can you think of that work in pairs to produce movement?• Biceps/triceps; hamstring/quadriceps

Types of Muscles

Muscles and tendons

• TendonsTendons are tough, fibrous cords of connective tissue that link skeletal muscles to bones.

• TendonitisTendonitis – inflammation of the tendon• Result of injury, overuse, or natural aging.

• Treatment mayincludes ultrasound or anti-inflammatory medication to reduce pain and swelling.

• Torn or Ruptured Tendon Torn or Ruptured Tendon – a sudden, powerful muscle contracting or wrenching injury can partially or completely tear a tendon. • Example: Kobe Byrant—torn Achilles tendon

Caring for Your Muscles• Get regular exercise

• Eat high protein foods to build muscle

• Practice good posture to strengthen back muscles.

• Use proper equipment and wear appropriate clothing to protect muscles during any physical activity.

• Warm up properly and stretch before exercising, and cool down after exercising to prevent injury.

• What are some good sources of protein for an after workout snack?

Understanding Muscular Problems• Muscle soreness from a strenuous workout is a

good thing, and although you may be sore, it is only temporary. Continuing to move will help get rid of soreness sooner.• More serious muscle injuries include:• Bruises Bruises – result from a blow to the body. Blood

vessels rupture and leak.• Treat with ice to reduce initial swelling.• Muscle strains or sprainsMuscle strains or sprains• Result when muscles are stretched or partially torn from

overexertion.• Apply ice to reduce swelling and rest affected area.

Strain vs. Sprain

• Sprains and strains are common injuries that share similar signs and symptoms, but involve different parts of your body.

• A sprain is a stretching or tearing of ligaments — the tough bands of fibrous tissue that connect one bone to another in your joints. The most common location for a sprain is in your ankle.

• A strain is a stretching or tearing of muscle or tendon. A tendon is a fibrous cord of tissue that connects muscles to bones. Strains often occur in the lower back and in the hamstring muscle in the back of your thigh.

The Human Body Book—Skeletal System

• “With its highly engineered joints, the living skeleton provides a framework of stiff levels and stable plates that permits a multitude of movements. Intimately connected with the muscular system, the skeleton also integrates functionally with the cardiovascular system—every second, millions of fresh blood cells pour out of bone marrow. A healthy diet that provides enough minerals, especially calcium, along with regular moderate exercise can reduce the risks of many bone and joint disorders.”

How the Skeletal System Works

• The skeletal system consists of 206 bones and connective tissue.

• Makes up approximately one-fifth of a healthy body’s weight. • Anatomically, the skeleton has two regions:• Axial—skull, vertebral column, and rib cage. • Consists of 80 bones.

• Appendicular—the “hanging” skeleton; bones in the limbs, the pectoral and pelvic girdles. • Consists of 64 in the upper and 62 in the lower.

• The connective tissues:The connective tissues:• Cushion the bones• Attach bone to bone• Attach bone to muscle

Functions of Functions of your skeletal your skeletal system:system:• Provide support for the body.

• Protect internal tissues and organs from damage

• Act as a framework for attached muscles.

• Allow movement of limbs and digits.

• Produce new red and white blood cells.

• Store fat and minerals, such as calcium and phosphorous.

Bones• Made up of living tissue formed into different layers. • Compact bone layer– hard and densely packed outer layer.

• Spongy bone layer – less dense bone with a network of cavities filled with red bone marrow, where blood cells are produced.

• Yellow bone marrow – stores fat.

• Bones are categorized by their shape:• Long bone

• Short bone

• Flat bone, and irregular bones

• Can you name a bone that fits each of these categories?

Connective Tissue• There are three types of connective tissue:• Cartilage Cartilage • Strong flexible tissue that acts as a cushion between two bones to

reduce friction.• It provides lightweight, flexible support at places in your body such

as the outer ear.• Also works as a “shock absorber”• All bones begin in the embryo as cartilage.

• LigamentLigament• Band of fibrous, slightly elastic tissue that attaches one bone to

another bone.• Attach to create joints. What are some joints can you think of?

• TendonTendon• Fibrous cord that attaches muscle to the bone.• What are some tendons that you can name?

Joints• Joints, or articulations, are points at which bones meet.• Some joints, such as the ones between the bones of the skull

do not move. These are called fixed joints. • Flexible joints are ones that move, these are called synovial

joints:• Ball-and-socket joints—allow for the greatest range of motion• Hinge joints—allows for forward and backward movement• Pivot joints—rotate on an axis• Saddle joints—allow bones to slide back and forth with limited

rotation• Gliding joints—Movement is limited by strong encasing

ligments• http://www.jeffsims.net/flash/skeleton.html

Caring for the Skeletal System• A healthy diet, exercise, protective gear, and regular

checkups are ways to care for your skeletal system.

• Foods high in calcium, vitamin D, and phosphorous help prevent skeletal disorders.

• During regular checkups, your doctor can screen for skeletal disorders like scoliosis.

• Weight-bearing activities such as walking or weight training helps bones stay strong.

• Wearing protective gear during sports reduces the risk of bone fractures.

Understanding Skeletal Problems

• Poor nutrition, infections, sports injuries, and poor posture can lead to problems with the skeletal system.

• Fractures Fractures – any type of break in the bone• Hairline fracture—parts of the bone do not separate.

• Greenstick fracture—crack on one side of a long bone cause by bending under force.

• Transverse fracture—a powerful force may cause a break across the bone width.

• Comminuted fracture—bone shatters into several fragments.

• Spiral fracture—bone breaks diagonally across the shaft.

• Compound fracture—when broken end of bone breaks through the skin.

http://video.about.com/orthopedics/Fractures-1.htm

• Injuries to jointsInjuries to joints• Can occur from overuse, strain, or disease. • Dislocation – when a bone slips out of place, tearing the

ligaments that attach the bone at the joint.• Torn cartilage – can result from a sharp blow to a joint or a

severe twisting of a joint.• Bursitis – results from the painful inflammation of bursa, a

fluid-filled sac that helps reduce friction in joints.• Bunions – painful swelling of the bursae in the first joints of

the big toes. Wearing ill-fitting shoes can make bunions worse.

• Arthritis – the inflammation of the joint, resulting from injury, natural wear and tear, or autoimmune disease.

• OsteoporosisOsteoporosis• Condition in which there is a progressive loss of bone

tissue.

• Bones weaken and become brittle.

• Common in older adults.

• Bone tissue loss is a natural part of aging, but healthful behaviors during your teen years can reduce your risk of developing osteoporosis later in life.

• Eating foods containing calcium, vitamin D, and phosphorous will help bones remain strong and healthy.

• Regular weight bearing activity, such as walking and weight training, stimulates bone cells to increase bone mass.

• http://youtu.be/F7p23Zro7LU